Exhibiting apparatus



March 7, 1933. G. A. HoLcoMBE EXHIBITING APPARATUS Filed uct. '7,I 1929 and adaptation.

Patented Mar. 7, 1933 iJNrrEo STATE-s `PMI-:1vT lorries GEORGE A. HOLCOIVIBE, OF SAN'ivDIEGO, CALIFORNIA EXHIBITING ArPARA'rUs Application filed October 7, 1929. Serial No. 397,761. Y

My invention relates to an exhibiting apparatus, and the objects of my invention are: First, to provide an exhibiting apparatus for the exhibition of lantern slides or stills; second, to provide an apparatus of' this class for the exhibition` of motion pictures; third,

to provide an apparatus of this class for the Y exhibition of Vphotographs orV halftone` reproductions thereof; fourth, to provide an apparatus of thisclass adapted for viewing various objects by means of reflection and magnification and by means of a concave reflecting surface or concave mirror; fifth, to provide an apparatus of this class whichA is readily adaptable for the various'purposes hereinbefore mentioned; sixth, to provide-an i exhibiting apparatus of this class which, in addition to showing a magnified image of a lantern slide, still, motion picture, photograph or reproduction thereof, wili also im'- part to such magnied image an appearance of being in relief; seventh, to provide an apparatus of this class which is adjustable throughout, and eighth,zto provide an apparatus of this class which is simple, economical of construction, durable, efficient in its action Viththese and other objects in view as will appear hereinafter, my invention Consists of certain novel features of construction, combination andarrangement of parts and portions as'will be hereinafter described in detail and particularly set forth in the appended claims, reference being had to the accompanying drawing and to the characters of reference `thereon which form part of this application in which: Y

Y Figure 1 is a perspective view of my exhibiting apparatus in its assembled relation ready for use; Fig. 2 is a -diagrammatical View showing the lines of reflection of my appara-tus and thernode of operation when using two mirrors, one concave and one plane mirror for refiecting purposes; Fig. 3 is a similar view showing Vthe applicationof the, same for the projection of stillsV or motionv i pictures or the exhibition of objects where only one reversal is required liig. 4 isa diagrammatical view which shows the geomet-A 0 rical adjustment of the two mirrors `when vertical pictures are shown; Fig. 5 is a diagrammatical view showingthegeometrical position of the magnified image whenthe two mirrors .are interchanged,that is, whenthe 1 planemirror becomes the exhibition mirror 55 instead `ofthe concave mirror; Fig. 6 isa fragmentary sectional view through 6-6 of Fig. 1; and Fig. isa substantially diagramy matical sectional view'throug'h 7'-7 of F ig.V 1.

Similar characters of reference refer to 60 several views of the drawing.

Frame '1, receiving grooves 2, sliding platform 3, screw 4, revoluble support 5, uprights 4 lsimilar parts and portions throughout the 6,"concave mirror 7, mirrorslide supports 8 65 and 9, shaft 10, projecting table 11, projecting tablevertical slide 12, journalv plates 13, -main longitudinal bar 14, and transverse bar 15, constitute the principali parts andportions of my exhibiting apparatus.

The frame'l is preferably rectangular'in shape and is provided with channel shaped side edges forming grooves 2 at the sides for the purposeof receiving a screen or a mirror.

These grooves k2 are of sufficient width to '75 l y permit the picture or mirror tobe positioned on a Vslight anglein the grooves, as desired.V yThis frame 1 is secured at its lower side ona plate 5 which is revolubly mounted in a recess in the upper side of the block 3 so that 80 'the' frame member 1 maybe turned to varying positions, as desired, relatively tothe block 3, and this` plate 5 is provided with a screw 4, whichlis adapted to screw into anyr one of several threadedholes 3a provided 85 in the lower surface of the recess in the block 3 `for holding the plate'in any Apositionde- Y siredv when'saidjscrew is tightened in the member 5. If desired, the frame 1 and plate j 5 may be removed from the block 3.

The block 3 is provided with groovesin its lower side which t overV the member 14s0 that this block 3 may be moved longitudinalf ly ralong said Vbar 14 tol anyjdesired'position carryingwith it the frame 1. ThisV bar 14 J5 is provided-at one end with a downwardly turned Vportion 5a. which formsA a base or `support for the outer end ofthe apparatus.`

Securedfto the opposite end ofthe .member thereto or transversely with the apparatus, and secured to the opposite ends of this bar 15 are the uprights 6 which extend below the same at 6a forming a base for this end 0f the apparatus.

Mounted between these uprights near their upper ends is a concave mirror 7 which is mounted on shafts 10 whichare pivoted in the supports 8 and 9 so that the mirror may be tilted' on the shafts 10 to varying positions and these supports 8 and 9HV are held in position on the uprights 6 by means of screws 9a, the inner ends of which extend into holes 6?) in the uprights 6, thus providing means for raising and lowering the mirrorv7 relative to the uprights 6. e Y

vMounted onthe one end -ofthe u-prights 6 on one side is a pairof plates 13 which are provided with lugswhich extend outwardly and in which are mounted the endsof the frame members 11 and at the opposite end 'of these frame members is a vertical frame 12 which is shiftable uponthe frame-members 11. The lower member 11 and the frame member 12 are provided with grooves 11a on their upper and innersides adapted to receive the edges of any objects placed thereon..

The purpose of the diagrammatical views 2 to 5, inclusive, -is to show how an observer from point E will view the magnified imageY ofan object, aphotograph or projected image represented by IJ which is reflected and magnified .by the concave mirror CM and indicates the mannerby which the observer Vmay control the magnification and shift of 'position of the magnified image in the center of the concave mirror. j

In the diagrammatical .view Fig. 2 the line ab krepresents the base upon which the apparatus is resting and corresponds to the bar 111 of Fig. 1 of the'drawing.` CM is a 1 dius of curvature is 36".

section of the meridian pla-neef alconcave spherical reflecting surface and represents the concave mirror 7 which is, for-the purpose of illustration, 8 in diameter.` Its ra- 18. CM is tilted to the left ofthe perpendicular at an angle of three degrees. IJ at 'right' angles to ab, rests' on ab at I and represents a photograph 5 high. PM lis a Vplane mirror 9.high and resting on ab at Kto the right of IJ facing .IJ and' CM.

PM is tilted to the left of the'perpendicular one and one-half degrees or half the number of degrees thatCMis tilted. -The first reflectionv of IJ will be in i PM v`asv at I2-J2 which is 6H behind PM ror 12 infront of CM.v Since'PM is tilted one and one-half degrees that portion of a?) beyond'K, or Kb, will move upwardly three degrees, so K?) becomesYK-LQ.. Since 'the focal length` of CM is 18, the magnification ratio of I2.J2,

412 in front' of CM and 6 fromits `focal point is determined by the formula eff/a2, where f is the focal length and fthe distance Its focal. length is `image'of the plane mirror and is 13.5 high as shown, and K-b2 will be reflected as Kik-b3, making an angle of three degrees with the base at K2. VSainte K2 is Qbehind CM the final magnified image of IJ will be 27 further along the line K2b3 making 36V in all. Therefore, I3-'J3, 36 behind CM, represents the final magnified image of IJ and is 15 high and parallel to CM.

The observer. from the point E by tilting the two mirrors CM and PM at the required angle, determined by visual observation, thereby places the final magnified image .in the center ofl the exhibiting mirror CM. rlhe observer sees the image through two mirrors, rst through CM and then through PM2. If the plan-e mirror is tilted half that `of the exhibiting mirror, then the final magnified image will occupy a plane parallel to the concave mirror and be practically free from distortion.

The diagrammatical view, Fig. 3, serves a double purpose, illustrating the application of this` apparatus to the projection of stills or motion pictures or the-exhibition of objects where only .one reversal is required. First, for projection purposes, the .line a?) represents the base upon which the apparatus is resting. CM is a spherical concave mirror 10 in diameter, XX the axis, A the vertex; CMhas Va radius-of 36, a focal length of 18. The bottom edge of GM is raised 8 above the base ab. IJ represents the projec; tion table lor screen placed 10 in front of CM and parallel to it.V The point P represents the position of the projection lens. The image at IJ is projected from behind and Vbelow/.Cliff and if the positive is placedV in the projection apparatus with the hlm side facing the light source, Athen the projected imageon IJ will be incorrect laterally, but

the magnified yand Areflected image will be V.projectiontable beingV tilted at angles that 'will center the magnified image in the middle ofthe concave mirror, but in this case both are tilted at the same angle in order that `the .screen will remain parallel to the mirror. -If IJ represents an object such as manufactured goods, or samples, laboratory specimens, etc., then the mirror only is tilted just sufficient to center the magnified image inthe concave mirror and the distance of IJ from CM will 'determine the magnification ratio, provided IJ remainsV at a distance from CM less than its focal length. 1

The diagrammatical view, Fig. 4, illustrates geometrically the adjustment of the two mirrors when vertical pictures are shown. CM is the concave mirror; PMl the plane mirror parallel to the former before the adjustment. The vertical picture instead of being placed directly beneath the concave mirror is placed at one-'side and inclined toward the other mirror at an angle of thirty degrees. IJ, the picture, forms .an angle of thirty degrees with XY and XY y'represents an imaginary line parallel to the axis of CM.V

PMl is then moved towards CM and IJ to an angle of thirty degrees, hence VI2--J 2 will be the reflection of IJ in PM, which is the positionrequired of the first reflection par- -allel to CM in order to be reflected and magnilied Without distortion.

v Fig. 5 illustrates geometrically the position of the magnified image when the two mirrors are interchanged. That is, when the plane mirror becomes the exhibiting mirror insteadV of the concave mirror.v CM is the concave spherical mirror having a focal length of 18. XX is the-axis. A the vertex of GM. Its diameter is 8". u IJ represents a photograph 5 high with its upper edge Vtouching the aids and placed 9 in front of CM. Its magnification ratio then will be two diameters and I1;-J1, 18"- behind CM, represents the first'reflection magnified by CM which the plane mirror PM will present to Athe observer at E. The plane mirror PM is tilted backwardly four degrees, thereby lowering that portion of the axis behind PM and refiected byl PM through an angle of eight degrees. The angleV XIV is eight degrees.

Hencethel final refiection and magnified image of IJ will be 185 behindCM2 with its upper edge touching VIV and at right I2--J 2 first through PM, thence through CM2. Both the final image and CM2 are parallel, which is the position vrequired to eliminate distortion.

It will be noted that the steps are identical in Figs. 2 and 5. Each, however,has its particular advantage according to the focal length of the concave mirror. The Fig. 2 represents the best arrangement for pictures '65 of Apostcard sizeand larger when the focal obtained when the projected ima-ge lies be-` VCM2 is therefiection of CM and PM and is'V 8 behind PM and is at right angles to IV.`

, that the frame 11 may be'moved backwardly .out ofthe way forshiftingthemirror 7 up and down .and when this frameis not in' use,

`or, if desired may` be removable from the members 13.` Y

The operation-of my exhibiting apparatus is as follows :Whenused foi` projection'purposes, by .removingthe frame -11 or turning I it out of the way,\the projection apparatus is thenfplaced behind the concavemirror with the lensy below 'thelow'er edge ofthe mirror and above thecross piece 15. Just sufficient throw is allowed `to cover thescreen. AAsec- 85 tion of the projection lfscreen'l material is placed in the frame 1 and thisframe is moved along theV barV 14 until the desired magnification is obtained. The magnification will be 0 tween the mirror and its focal point. If only a few persons `are viewing the image, 'then the largest-'magnification possible may be used 5' but if a larger number are viewing it,

then a smaller magnification must be used in order that those that are farthest removed from the apparatus may see the-.entire image behind the mirror. The position ofthe magnified image maybe adjustedtosuit theeye level of the observer; the image is lowered byl tilting the top of the concave mirror backward,`and is'raised by tilting the top of the mirror forward.V The film, still, orlantern slide must be projected with the film side of the positive facing the light source in order @05 that thefinal image will'be correct laterally y as the mirror :will provide but one-reversal. l

When using theiappara'tus for exhibiting horizontal photographs or reproductions of the same, the picture is placed in a groove ofthe projection'table 11 and the position is as shown in Fig.. l of the drawings,-and

lithe sliding member 12 lbrought in contact l Awith it, which vprovides a second 'groove to -fassist' in holding the picture. `The upper U5 edge of the picture should 'be close to the v lower edge of the mirror.` The amount of magnification is obtained. by lsliding the frame 1 which has in this case a plane mirror) in the Vgroove 2 along the cross piece .li-2.0 lt'and the image is centered in the concave mirror bygtilting either offboth mirrors, asV explainedin the above paragraph. l, y

Y When theapparatus isused for exhibiting vertical pictures, the following operation isl desirable: If a long, vertical picture'is placed on the projectiontablell, wheny in the position shown in Fig. 1 ofthed-rawing, the lower edgef of the picture will be so far removed :from the axisofthe mirror that bothspheri'- 1130 aio H objects which are not pictures, such as oresamples, manufactured goods, `laboratory samples, etc., whereY the object may be-seen as a whole and magnified, the frame 1 is removed from the platform by loosening and removing the bolt 5, then leaving the plat form clear. rrIhenthe platform may be used to support the object to be exhibited.V The 'reflected image will be reversed laterally. If v two reversals are required, then theoblject is placed below the concave mirror on the cross piece '15, after turning=the projection table out of the way,` and theplane mirror in framel' used for the exhibition of the object.v .i

Though I haveshown and described a particular construction, combination and arrangement of parts and portions, I do not wish to be limited .to this particular construction, combination and arrangement, but desire to include in the scope of my invention the construction, combination and arrangement substantially as set forth in the appended claims. d i v Having thus described my invention, what I claim as new and desire to secure by Letters Patent is: u 1=. VIn an exhibiting-apparatus, a frame including a pair ofspaced apartuprights, a concave mirror pivotallyr supported on a horizontal axis positioned intermediate its upper and lower sides between said uprights, aplan-e mirror receiving-frame supported on said frame relative to, and facing, said concave mirror, at a dista-nceffrom said concave mirror lessthan its focal length, vand another frame, or picture holder, pivotally supported yon said frame slightly below said lconcave' ymirror with its front facing the Afront of said plane mirror frame.

2. Inan exhibiting apparatus, a'frame including a pair of spaced apart uprights, a concave mirror pivotally supported on a horizontal axis ,positioned.intermediate its upper and `lower 'sides between said up- 'rights, means for adjusting, said concave mirror in upwardly and downwardly shifted positions, a plane'mirror receiving-frame sliiftably and rotatably supported on said v frame relative to, and facing, sai-d concave mirror, said-fiameb-eing shiftable from said frame slightly below said concave mirror and with its front facing the front of said plane mirror frame.

3. In an apparatus of the class described a main frame, a tiltabley concave mirror mounted for adjustment upwardly and downwardly on uprights secured to said main frame, a rotatably and shiftably mounted frame provided with slots forreceiving a plane mirror, positionedfacing said concave mirror, and on said main frame, means for securing said rotatable frame in saidl adjusted position, and an opaque object receiving frame pivotally supported on one end on one of the uprights supporting said concave mirror slightly below said concave mirror and facing the front of said plane` mirror receiving-frame.

concave mirror, a plane mirror receiving;

frame Vshiftably and rotatably supported relatively to said concave mirror so that it faces said concave mirror, means for supporting and adjusting said concave mirror in upwardly and downwardly shifted positions and an opaque object receiving and supporting frame pivota-lly supported aty one end slightly below said concavewmi'rror, and its front facing the fi'ont of said plane mirror receiving frame.

5. An exhibiting apparatus consisting of a frame, a concave mirror tiltably mounted thereon, a plane mirror receiving frame shiftably mounted onV said first-mentioned frame so that said plane mirror faces said yconcave mirror at a distance less than its focal length therefrom, and another frame lfor an opaque picture-holder for 4holding a picture facing said plane mirror, positioned slight-lybelow said concave mirror on said frame.

' 6. An exhibiting apparatus consisting of a frame, a concave mirror tiltably mounted thereon, a .plane mirrorv -shiftably mounted facing said concave mirror positioned at'a distance from said concave mirror less than' thenfocal length ofsaid concave mirror, and an opaque picture frame sliiftably mounted on said first-mentioned frame facing said plane mirror and positioned slightly below -1 concave mirror through a distance less thanV Yits focal length, and another/frame, or pictureholder, pivotally supported on said I` have hereunto setl 

